The purpose of this project is to investigate the role of the central nervous system in behavior. In some experiments monkeys (Macaca mulatta) are used to examine the extent to which the cardiovascular system can be modified by instrumental conditioning. In other experiments we examined age-related behavioral changes in rats and mice in a variety of tasks, including motor performance, thermoregulation, learning and memory. Biochemical and electrophysiological methods assess neurobiological correlates and mechanisms of age-related behavioral dysfunctions. Studies are also conducted which attempt to modulate behavioral aging through pharmacological, nutritional, and environmental manipulations, including use of cholinergic agonist drugs, dietary restriction, brain stimulation and exercise.